Be cautious if you are using a Python install that is managed by your operating
system or another package manager. get-pip.py does not coordinate with
those tools, and may leave your system in an inconsistent state.

The pip developers are considering making --user the default for all
installs, including get-pip.py installs of pip, but at this time,
--user installs for pip itself, should not be considered to be fully
tested or endorsed. For discussion, see Issue 1668.